Rebase/merge against another branch overriding conflicts with your own branch

Source

Quite often I find myself in a situation when I need to rebase my local feature branch containing the latest code against the master, but running git rebase master generates a bunch of conflicts that I am expected to fix manually, though I know that my local feature branch has the latest and greatest and I simply want the changes in my feature branch overwrite the corresponding files in master each time such conflict arises. This usually happens when I am the only committer on the project.

Changes in my-branch overwrite changes in master

If rebasing:

git checkout my-branch
git rebase -Xtheirs upstream/master

If merging (the meaning of -Xtheirs and -Xours is reversed):

git checkout my-branch
git merge -Xours upstream/master

Changes in master overwrite changes in my-branch

Do the opposite, i.e. where it says -Xtheirs do -Xours and visaversa.

Start by reviewing the linked source and the issue's Git rebase and merge examples. Check the repository's existing resource organization to determine where this material belongs; done means the guidance is incorporated in the appropriate resource location without changing the documented commands.